Mechanical Engineering MCQs

A simply supported beam ‘A’ of length l, breadth b, and depth d carries a central point load W. Another beam ‘B’ has the same length and depth but its breadth is doubled. The deflection of beam ‘B’ will be __________ as compared to beam ‘A’.

by
one-fourth
one-half
double
four times
✅ The correct answer is option B.

A rigid body, under the action of external forces, can be replaced by two masses placed at a fixed distance apart. The two masses form an equivalent dynamical system, if

by
the sum of the two masses is equal to the total mass of body
the centre of gravity of the two masses coincides with that of the body
the sum of mass moment of inertia of the masses about their centre of gravity is equal to the mass moment of inertia of the body
all of the above
✅ The correct answer is option D.

A moving fluid mass may be brought to a static equilibrium position, by aplying an imaginary inertia force of the same magnitude as that of the accelerating force but in the opposite direction. This statement is called

by
Pascal’s law
Archimede’s principle
D-Alembert’s principle
none of these
✅ The correct answer is option C.

A shaft is subjected to a maximum bending stress of 80 N/mm2 and maximum shearing stress equal to 30 N/mm2 at a particular section. If the yield point in tension of the material is 280 N/mm2 and the maximum shear stress theory of failure is used, then the factor of safety obtained will be

by
2.5
2.8
3
3.5
✅ The correct answer is option B.